The Opposition on Thursday stepped up its attack on the government over the Agnipath scheme amid protests against it in several parts of the country and demanded that it be scrapped, even as official sources asserted that no change is being done to the Army's regimental system under the new initiative.

While Congress leader Rahul Gandhi urged Prime Minister Narendra Modi to listen to the voice of unemployed youths and not take 'agnipareeksha (trial by fire)' of their patience by making them walk on Agnipath, Samajwadi Party president Akhilesh Yadav called the move "negligent" and potentially "fatal" for the country's future.

Trains were set afire, window panes of buses smashed and passersby, including a ruling BJP MLA, pelted with stones in Bihar by Army job aspirants whose protest against the short-term recruitment scheme continued for the second consecutive day.

Protests against the scheme also took place in Haryana and Uttar Pradesh.

Hundreds of young people took to the streets in Haryana's Gurugram, Rewari and Palwal while scores of youngsters in Uttar Pradesh's Bulandshahr and Ballia districts staged protests against it.

Amid the protests, government sources said no change is being done to the Army's regimental system under it and the numbers of personnel to be recruited in the first year of its roll out would only make up three per cent of the armed forces.

The scheme is aimed at increasing opportunities for youths to serve in the armed forces and the recruitment of the personnel under it will be around triple of the current enrolment in the armed forces, they said without specifying the duration of comparison.

On the criticism that the short-duration tenure of 'Agniveers' will harm the effectiveness of the armed forces, the sources said such a system exists in several countries, and hence, it is already "tested out and considered best practice for an agile army".

The Opposition came down heavily on the government over the scheme and demanded a rollback.

"No rank, no pension, no direct recruitment for 2 years, no stable future after four years, no respect shown by the government for the army," Gandhi said in a tweet in Hindi, attacking the Centre over the scheme.

"Listen to the voice of unemployed youths of the country, don't take 'agnipareeksha' of their patience by making them walk on 'Agnipath', Mr. prime minister," the former Congress chief said.

In a tweet in Hindi, Priyanka Gandhi said there are many dreams for the future in the eyes of those preparing for recruitment in the armed forces such as serving the country and their parents.

"What will the new army recruitment scheme give them? After 4 years, no job guarantee, no pension facility = no rank, no pension. @narendramodi ji don't crush the dreams of the youth," she said.

Questioning various provisions of Agnipath, BJP MP Varun Gandhi said it will give rise to more disaffection among the youths and asked the government to make its stand clear.

In a letter to Defence Minister Rajnath Singh, Varun Gandhi said the young population has shared their questions and doubts with him about the radical changes in the soldiers' recruitment process which also proposes that the 75 per cent of the recruits under the scheme will retire after four years of service without pension.

The Left parties demanded that the Agnipath scheme be scrapped and be taken up in Parliament for discussion, alleging that it does a "disservice" to India's national interests.

"The Polit Bureau of the CPI(M) strongly disapproves the 'Agnipath' scheme that does disservice to India's national interests. Professional armed forces cannot be raised by recruiting 'soldiers on contract' for a period of four years. This scheme, to save pension money, severely compromises the quality and efficiency of our professional armed forces," CPIM general secretary Sitaram Yechury said in a tweet.

CPI general secretary D Raja tweeted, "Finding jobs has become literally a 'Path of Fire' under Modi. Govt is trying to hoodwink the restive youth by #AgnipathScheme. It'll make our army contract based & jeopardise the future of our youth. It should be withdrawn immediately! Youth deserve proper, secure jobs!"

Delhi Chief Minister Arvind Kejriwal appealed to the central government to give the youth the chance to serve the country throughout their life, not just four years.

Samajwadi Party president Yadav also hit out at the central government over the Agnipath scheme.

"The security of the country is not a short-term or informal issue; it expects a very serious and long-term policy. The negligent attitude that is being adopted regarding military recruitment will prove to be fatal when it comes to the protection of the future of the country and the youth, Akhilesh said in a tweet.

Bahujan Samaj Party (BSP) supremo Mayawati hit out at the Union government over the scheme, terming it "unfair towards rural youth". She urged the Centre to "reconsider" its decision immediately.

The government unveiled Agnipath on Tuesday - calling it a "transformative" scheme- for the recruitment of soldiers in the Army, Navy and the Air Force, largely on a four-year short-term contractual basis.

Under the scheme, around 46,000 soldiers will be recruited this year between the ages of 17-and-a-half years and 21 years into the three services, the defence ministry said.